Evidence map›Paper›PMID 26574453›Full record

ArticleJournal of chemical theory and computation2015

ff14SB: Improving the Accuracy of Protein Side Chain and Backbone Parameters from ff99SB.

James A Maier, Carmenza Martinez, Koushik Kasavajhala, Lauren Wickstrom, Kevin E Hauser, Carlos Simmerling

Abstract read
In one paragraph

Article in Journal of chemical theory and computation, 2015. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 5,060 papers.

0numbers the graph read from it
0cells of the map it votes in
5,060citing papers in PubMed
145.1field-weighted citation impact, top 1% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

5,060 citing papers in PubMed, 10,737 citations in OpenAlex.

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5,000 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

6 authors at 1 institution in 1 country.

James A MaierGraduate Program in Biochemistry and Structural Biology, ‡Department of Chemistry, and §Laufer Center for Physical and Quantitative Biology, Stony Brook University , Stony Brook, New York 11794, United States.
Carmenza MartinezGraduate Program in Biochemistry and Structural Biology, ‡Department of Chemistry, and §Laufer Center for Physical and Quantitative Biology, Stony Brook University , Stony Brook, New York 11794, United States.
Koushik KasavajhalaGraduate Program in Biochemistry and Structural Biology, ‡Department of Chemistry, and §Laufer Center for Physical and Quantitative Biology, Stony Brook University , Stony Brook, New York 11794, United States.
Lauren WickstromGraduate Program in Biochemistry and Structural Biology, ‡Department of Chemistry, and §Laufer Center for Physical and Quantitative Biology, Stony Brook University , Stony Brook, New York 11794, United States.
Kevin E HauserGraduate Program in Biochemistry and Structural Biology, ‡Department of Chemistry, and §Laufer Center for Physical and Quantitative Biology, Stony Brook University , Stony Brook, New York 11794, United States.
Carlos SimmerlingGraduate Program in Biochemistry and Structural Biology, ‡Department of Chemistry, and §Laufer Center for Physical and Quantitative Biology, Stony Brook University , Stony Brook, New York 11794, United States.
Stony Brook University · US

Funding

New Solvent Models, Sampling Methods and Maintenance of Amber SoftwareR01GM107104 · NIGMS · STATE UNIVERSITY NEW YORK STONY BROOK · PI SIMMERLING, CARLOS · 2013 to 2020
$2.4M
ENHANCED MEAN-FIELD SIMULATIONS OF ANTIBODY CDR LOOPSR01GM061678 · NIGMS · STATE UNIVERSITY NEW YORK STONY BROOK · PI SIMMERLING, CARLOS · 2000 to 2009
$1.8M
NIGMS NIH HHS GM061678NIGMS NIH HHS GM107104NIGMS NIH HHS R01 GM061678NIGMS NIH HHS R01 GM107104
6 · The paper itself

Abstract

Molecular mechanics is powerful for its speed in atomistic simulations, but an accurate force field is required. The Amber ff99SB force field improved protein secondary structure balance and dynamics from earlier force fields like ff99, but weaknesses in side chain rotamer and backbone secondary structure preferences have been identified. Here, we performed a complete refit of all amino acid side chain dihedral parameters, which had been carried over from ff94. The training set of conformations included multidimensional dihedral scans designed to improve transferability of the parameters. Improvement in all amino acids was obtained as compared to ff99SB. Parameters were also generated for alternate protonation states of ionizable side chains. Average errors in relative energies of pairs of conformations were under 1.0 kcal/mol as compared to QM, reduced 35% from ff99SB. We also took the opportunity to make empirical adjustments to the protein backbone dihedral parameters as compared to ff99SB. Multiple small adjustments of φ and ψ parameters were tested against NMR scalar coupling data and secondary structure content for short peptides. The best results were obtained from a physically motivated adjustment to the φ rotational profile that compensates for lack of ff99SB QM training data in the β-ppII transition region. Together, these backbone and side chain modifications (hereafter called ff14SB) not only better reproduced their benchmarks, but also improved secondary structure content in small peptides and reproduction of NMR χ1 scalar coupling measurements for proteins in solution. We also discuss the Amber ff12SB parameter set, a preliminary version of ff14SB that includes most of its improvements.

Indexed as

Amino AcidsMagnetic Resonance SpectroscopyMolecular Dynamics SimulationPeptidesProteinsProtein Structure, SecondaryQuantum TheoryThermodynamicsAmino AcidsPeptidespolyalanineProteins

Identifiers

PMID26574453
PMCPMC4821407
OpenAlexW2404280981

What OpenQuestion holds

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LicenceTDM
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.